Zia, a two times former prime minister and leader of the Bangladesh Nationalist Party (BNP), went to the Supreme Court to seek a suspension of the proceedings, saying the lower court judge who has been hearing her cases was appointed illegally.
But a Supreme Court bench headed by chief justice Md Muzammel Hossain dismissed her appeals, allowing the trials to go ahead in a special court that deals with graft cases, her lawyer Sanaullah Miah said.
“We have not got justice,” Miah told AFP, adding Zia’s trials in the graft court could still be delayed because the Supreme Court has not yet disposed of two more appeals against the charges.
But Attorney General Mahbubey Alam told reporters that Zia’s trial could go ahead despite the appeals.
“There is no bar for running Khaleda Zia’s trial,” he said, adding the appeals were aimed at delaying the proceedings.
Earlier the high court had rejected similar appeals by Zia, prompting her lawyers to move to the highest court in a last-ditch attempt to stop the trials.
Prosecutors have accused Zia’s lawyers of time-wasting, saying hearings in the case have been delayed dozens of times.
Zia and three of her aides are accused of syphoning off 31.5 million taka (about $400,000) from a charitable trust named after her late husband Ziaur Rahman, a former president who was assassinated in 1981.
She is also accused of leading a group of five people, including her eldest son, in embezzling 21.5 million taka ($277,000) — funds which were meant to go to an orphanage set up in memory of her late husband.
Zia, who has been excused from attending the trial, has called the charges politically motivated and aimed at destroying the BNP, which has vowed to topple the government of her arch rival Prime Minister Sheikh Hasina.
The 69-year-old leader was charged just weeks after Hasina was re-elected in a January 5 general election which the centre-right BNP and its 18 opposition allies boycotted and denounced as a farce.
The charges date back to Zia’s last term as premier from 2001 to 2006 and can carry a life sentence, prosecutors have said.
Zia, who first became premier in 1991, has a notoriously poisonous relationship with Hasina — an enmity which dates back three decades
The January polls effectively became a one-horse race after the BNP and other opposition parties refused to field candidates over rigging fears.
Nearly 200 people died in political violence surrounding the election as the opposition and security forces fought pitched battles